[llvm] [ElimAvailExtern] Add an option to allow to convert global variables in a specified address space to local (PR #144287)

[Shilei Tian via llvm-commits]

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@@ -88,9 +94,32 @@ static void convertToLocalCopy(Module &M, Function &F) {
   ++NumConversions;
 }
 
+static void convertToLocalCopy(Module &M, GlobalValue &GV) {
+  assert(GV.hasAvailableExternallyLinkage());
+  std::string OrigName = GV.getName().str();
+  std::string NewName = OrigName + ".__uniq" + getUniqueModuleId(&M);
+  GV.setName(NewName);
+  GV.setLinkage(GlobalValue::InternalLinkage);
+  ++NumConversions;
+}
+
 static bool eliminateAvailableExternally(Module &M, bool Convert) {
   bool Changed = false;
 
+  // Convert global variables in specified address space before changing it to
+  // external linkage below.
+  if (ConvertGlobalVariableInAddrSpace.getNumOccurrences()) {
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shiltian wrote:

Just thought it might be less efficient.

https://github.com/llvm/llvm-project/pull/144287